The present invention relates to a fabric material having a first finish on a first side of said fabric material and a second different finish on an opposite second side of said fabric material. The invention also relates to a method of treating a fabric and a window covering comprising such a fabric.
One method of treating a fabric material for a window covering product is inter alia known for curtains and shades, in particular of pleated blinds, such as described in the U.S. Pat. No. 3,946,786. Pleated blinds like the ones described in the mentioned patent, usually incorporate fabric material that is coloured on the first side to enhance the decorative function of such window covering product, while being metallized on the opposite second side for reflecting sunlight or heat.
One method for producing such fabric material involves metallizing by vacuum deposition, while colourinq is done in a separate printing operation after said metallizing.
A disadvantage of such a method is that although being reasonably effective, such a method is rather expensive, whereas the quality of the window covering product, particularly the durability of the metallization, especially in hostile environments has been somewhat disappointing. Chemical and mechanical damage of metallized fabrics is often experienced in greenhouse or skylight installations where extreme heat and humidity conditions usually prevail. Also, domestic window cleaning agents if spilt on the metallized side of known fabric window covering products have been found to have aggressive components which can damage the metallized layer. Finally, also insect excrements often found in these overhead installations can do damage to the reflective layer.
According to the present invention there is provided a fabric comprising a fabric material having opposite sides; a first finish on one side and a second finish on the other side; said first finish comprising a mixture including a first pigment having a first particle size and said second finish comprising a mixture including a second pigment having a second particle size, said second particle size being larger than said first particle size.
Such a fabric can overcome many of the above disadvantages. In a preferred fabric, according to the invention, the first pigment is darker than said second pigment.
Advantageously the second pigment is light reflective and may, for example, be mica.
Desirably said first pigment has a particle size of 1 to 10 microns, preferably 1 to 3 microns, and said second pigment has a particle size of 10 to 180 microns, preferably 10 to 60 microns.
The chemical and mechanical properties of the fabric materials according to the invention are superior to those of traditional metallized fabrics and result in appropriate reflective values. As an example, the fabric of the invention can be resistant to moisture, condensation, window cleaning products, insect excrements and extreme temperature conditions. So, the product of the invention if used as a reflective window covering product, has substantially equal heat and light reflective properties to conventional metallized fabric, but at the same time has an improved resistance against damage and wear during use.
The invention also provides a method of treating a fabric material to obtain a first finish on a first side of said fabric material and a second different finish on an opposite second side of said fabric material, characterized in that said first and second finishes are applied simultaneously by a single operation.
Such a method of treating can achieve more economicalxe2x80x94manufacturing of fabric material for window covering products and provide more economical, and at the same time more aesthetically pleasing window covering products.
The use of a single operation according to the invention provides an improvement as the fabric is subjected to shorter treatment which is also more economical. Such single operation may comprise the steps of providing said fabric, material having a hydrophilic character, applying a fluid dispersing medium to the second side of said fabric material, said fluid dispersing medium comprising first pigmentxe2x80x94particles for providing said first finish, said first pigment particles having a first size, second pigment particles for providing said second finish, said second pigment particles having a second size larger than said first size, allowing said first pigment particles to permeate substantially through said fabric material to the first side while at least said second pigment particles remain substantially on the second side, and subsequently drying said fabric material.
With such single operation the fabric material is favourably used to separate the second pigment particles which are destined for the second side only, from the first pigment particles. The hydrophilic character of the fabric material, the properties of the fluid dispersing medium and the size difference between the discrete pigment particles together account for the effect that is achieved by the invention.
If different coloured pigment particles are used it should be understood that darker pigment particles if available in a sufficient concentration will usually dominate any light coloured pigment particles. With the fabric material for window covering products referred to herein above, light reflective or metal second pigment particles would be desired on the second side of the fabric material. If such reflective second pigment particles in the method of the invention are combined with somewhat darker coloured first pigment particles on the same side of the fabric material, the additional benefit is obtained that also the light reflective second side obtains the colour of the first side of the fabric material, which is advantageous from a decorative point of view. Such improvement can be obtained, while achieving at the same time appropriate reflective properties. Many types of fabric materials and pigment particles are suitable in practising the invention. Similarly, several conventional coating techniques such as printing by a rotary screen printing process may be adapted successfully to practise the present invention.
According to one embodiment of the invention, said reflective properties may be obtained by using pearlescent or iridescent second pigment particles such as mica. Fabric materials having a pearlescent side may be used in window coverings referred to herein above as a replacement for metallized fabrics in known pleated blinds and roller shades. By using mica particles with the method of the present invention the majority of the above problems can be overcome. A further advantage of a fabric material for a window covering product according to such an embodiment is a reflective side that can be colour matched to the nonreflective side, but still offer the same reflective properties. This decorative advantage is not available to metallized fabrics which always have a distinct gray or metal-like appearance on their reflective sides, obviously other inorganic particles or alternatively reflective metal particles may be used if different effects are sought.
The invention also comprises embodiments in which additional decorative or functional patterns are printed on the fabric material. This may be effected either prior to or subsequent to the single operation of the present invention.
A window covering product in accordance with the present invention may readily be made such that the second side is substantially of the colour as the first side. By use of the method the possibility arises to achieve the light reflective properties with a coloured finish. Such a window covering product can thus have different aesthetic and physical properties on opposite sides while being substantially of a matching colour.
A particular advantage as opposed to conventional metallized fabric is the ability of applying a subsequent crushing treatment for decorative purposes.